A power tool having a quick clamping device is generally known from US 006569001 B2. The described hand-held tool is an angular grinder equipped with a hollow output mandrel therein, wherein a clamping device is mounted in the hollow mandrel and is movable between a clamped position and a released position along the axial direction of the mandrel. The described clamping device includes a clamping flange which is provided with a threaded pin in the middle thereof and is used for cooperating with an opposite flange on the end of the hollow mandrel shaft to clamp a working element therebetween. A thrust component mated with the threaded pin is further arranged in the hollow mandrel. At the clamped position, the threaded pin is screwed into the thread of the trust component and is held in the clamped position under the action of the spring force, and at the released position, the thrust component pushes the threaded pin so as to drive the clamping flange to overcome the spring force and disengage from the surface of the clamped working element. Because there is no frictional force between the clamping flange and the clamped working element when they rotate relative to each other, the threaded pin of the clamping flange can be manually screwed out of the thrust component without the aid of any accessories so that the working element can be replaced conveniently.
Though, for this kind of clamping device, the working element can be substantially clamped to the output shaft of the hand-held tool without any auxiliary tools, however, this clamping device is only suitable for clamping the rotatably driven working element. If the working element is driven by a vibration device such that the working element sways forward and rearward along a longitudinal axis of the output shaft, then this results in a greater transilient torque and a very great impaction occurring in the two rotation directions and it is effectively impossible to ensure the working element to be clamped sufficiently and firmly by means of a known clamping device.